Today’s high-calorie diets begin damage decades before signs appear
Despite the implication of our headline, this news isn’t really about burgers.
Burgers — especially grass-fed beef or bison patties — can play a modest role in generally healthful, whole-food diets.
Instead, new findings link greater brain decay to consuming the amount of excess calories found in a fast-food burger, fries, and soda meal.
On average, people whose eating patterns resemble the so-called Western or “standard American" diet now consume a whopping 650 more daily calories than they did during the 1970s — a quarter of the average daily calorie needs for men and just under a third of women's needs.
Growing evidence links calorie-heavy Western/American diets — ones high in sugars, white-flour goods, cheap vegetable oils, grain-fed meats, processed foods, and fast foods — to higher risks for dementia.
Epidemiological (population-health) studies link excess belly fat or “central obesity” — which is promoted by the standard Western/American diet — to higher dementia risks: see our 2008 report, Big Bellies Fuel Brain Fog.
Why would that link exist? Excess abdominal fat emits chemicals that reduce blood flow in the brain, damage brain cells, reduce metabolic (calorie-burning) rates, and aggravate inherited genetic vulnerabilities to dementia.
This may help explain why Alzheimer’s disease and other forms of dementia are the fifth leading causes of death among Americans aged 65 or older, and why the risk of death from Alzheimer’s rose by an alarming 39% between 2000 and 2010.
Now, the results of a large, well-designed epidemiological study suggest that Western-style eating patterns begin to damage brain health long before any signs appear.
Australian study links high-calorie Western diets to early brain damage
Scientists from the Australian National University reviewed the results of about 200 international studies that tracked the brain and overall health (Cherbuin N, Walsh EI 2019).
But their review focused on exceptionally good data derived from a prior Australian study designed to detect the long-term effects of diet and lifestyle, which followed 7,484 people of various ages for 12 years.
That Aussie study included participants who occupied one of three age brackets — 20–24, 40–44, or 60–64 years — when they enrolled. Over the course of the 12-year study, information on each participant’s health and lifestyle was collected every four years.
Professor Nicolas Cherbuin, lead author of the new data analysis, said its results showed that brain health can decline much earlier than previously thought — due in large part to calorie-heavy Western-style diets and sedentary lifestyles.
Dr. Cherbuin expressed their findings in stark terms: “People are eating away at their brain with a really bad fast-food diet and little-to-no exercise.”
Study was aimed at clarifying the diet-dementia link
Professor Cherbuin noted that the link between type 2 diabetes and rapid deterioration of brain function is well established.
However, as he said, “… our work shows that neurodegeneration, or the loss and function of neurons, sets in much, much earlier — we've found a clear association between this brain deterioration and unhealthy lifestyle choices.”
His team's analysis put most of the blame on the diabetes-promoting effects of calorie-heavy Western/American diets: “It is of particular concern that the pathological cascade leading to higher FBG [fasting blood glucose] and ultimately T2D [type II diabetes] typically begins decades before and starts impacting cerebral health and cognition from its onset.”
As Cherbuin said, “… advice for people to reduce their risk of brain problems, including their risk of getting dementia, is most commonly given in their 60s or later, when the ‘timely prevention’ horse has already bolted.”
Cherbuin underlined their alarming finding in a press release: “The damage done is pretty much irreversible once a person reaches midlife, so we urge everyone to eat healthy and get in shape as early as possible — preferably in childhood but certainly by early adulthood.”
(Despite that conclusion, there is some evidence that diet and lifestyle changes later in life can reduce the risk for dementia: see Diet and Lifestyle May Cut Dementia Risk by 35%.)
The conclusion of the Aussie team’s report urged swift action: “… policy responses and interventions aimed at preserving neurocognitive capital [thinking/memory capacity] and slowing cognitive decline in aging should be initiated as early as possible and preferably in childhood or early adulthood and be sustained across the adult lifespan.”
“People eating too much of the wrong kind of food, particularly fast food, is the other big worry”, said Cherbuin. “As a society, we need to stop asking, ‘do you want fries with that?’.”
- Bello-Chavolla OY, Antonio-Villa NE, Vargas-Vázquez A, Ávila-Funes JA, Aguilar-Salinas CA. Pathophysiological mechanisms linking type 2 diabetes and dementia: Review of evidence from clinical, translational and epidemiological research. Curr Diabetes Rev. 2019 Jan 15. doi: 10.2174/1573399815666190129155654. [Epub ahead of print]
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